$KALU
KAISER ALUMINUM CORP Stock $kalu

$kalu Overview Financials Valuation SEC Filings Company Website

2019 Q2 Form 10-Q Financial Statement

#000081159619000044 Filed on July 26, 2019

Income Statement

Concept	2019 Q2	2018 Q2
Revenue	$375.3M	$415.4M
YoY Change	-9.65%	16.59%
Cost Of Revenue	$303.5M	$343.4M
YoY Change	-11.62%	18.58%
Gross Profit	$71.80M	$72.00M
YoY Change	-0.28%	7.95%
Gross Profit Margin	19.13%	17.33%
Selling, General & Admin	$27.20M	$26.40M
YoY Change	3.03%	0.38%
% of Gross Profit	37.88%	36.67%
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$12.10M	$10.90M
YoY Change	11.01%	14.74%
% of Gross Profit	16.85%	15.14%
Operating Expenses	$39.40M	$37.30M
YoY Change	5.63%	1.08%
Operating Profit	$32.40M	$34.70M
YoY Change	-6.63%	177.6%
Interest Expense	$5.800M	$5.700M
YoY Change	1.75%	3.64%
% of Operating Profit	17.9%	16.43%
Other Income/Expense, Net	-$100.0K	-$500.0K
YoY Change	-80.0%	400.0%
Pretax Income	$26.50M	$28.50M
YoY Change	-7.02%	313.04%
Income Tax	$7.300M	$7.800M
% Of Pretax Income	27.55%	27.37%
Net Earnings	$19.20M	$20.70M
YoY Change	-7.25%	340.43%
Net Earnings / Revenue	5.12%	4.98%
Basic Earnings Per Share	$1.19	$1.24
Diluted Earnings Per Share	$1.18	$1.22
COMMON SHARES
Basic Shares Outstanding	16.06M	16.69M shares
Diluted Shares Outstanding	16.24M	16.91M shares

Balance Sheet

Concept	2019 Q2	2018 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments	$146.8M	$235.9M
YoY Change	-37.77%	1.33%
Cash & Equivalents	$122.4M	$164.0M
Short-Term Investments	$114.6M	$217.8M
Other Short-Term Assets	$21.70M	$29.00M
YoY Change	-25.17%	8.21%
Inventory	$231.1M	$177.2M
Prepaid Expenses
Receivables	$178.1M	$191.2M
Other Receivables	$25.10M	$18.90M
Total Short-Term Assets	$649.7M	$704.8M
YoY Change	-7.82%	14.45%
LONG-TERM ASSETS
Property, Plant & Equipment	$613.8M	$584.2M
YoY Change	5.07%	5.81%
Goodwill	$44.00M	$18.80M
YoY Change	134.04%	0.0%
Intangibles
YoY Change
Long-Term Investments
YoY Change
Other Assets	$41.30M	$40.20M
YoY Change	2.74%	11.67%
Total Long-Term Assets	$772.4M	$719.0M
YoY Change	7.43%	-6.73%
TOTAL ASSETS
Total Short-Term Assets	$649.7M	$704.8M
Total Long-Term Assets	$772.4M	$719.0M
Total Assets	$1.422B	$1.424B
YoY Change	-0.12%	2.68%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$101.3M	$132.0M
YoY Change	-23.26%	56.77%
Accrued Expenses	$68.60M	$54.90M
YoY Change	24.95%	-14.75%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00
YoY Change
Long-Term Debt Due	$1.200M
YoY Change
Total Short-Term Liabilities	$178.9M	$194.1M
YoY Change	-7.83%	24.18%
LONG-TERM LIABILITIES
Long-Term Debt	$370.9M	$370.0M
YoY Change	0.24%	0.22%
Other Long-Term Liabilities	$24.70M	$24.80M
YoY Change	-0.4%	19.23%
Total Long-Term Liabilities	$395.6M	$394.8M
YoY Change	0.2%	1.23%
TOTAL LIABILITIES
Total Short-Term Liabilities	$178.9M	$194.1M
Total Long-Term Liabilities	$395.6M	$394.8M
Total Liabilities	$675.8M	$662.8M
YoY Change	1.96%	7.27%
SHAREHOLDERS EQUITY
Retained Earnings	$177.3M	$123.1M
YoY Change	44.03%	26.13%
Common Stock	$1.059B	$1.055B
YoY Change	0.43%	0.51%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$448.1M	$378.0M
YoY Change	18.54%	9.88%
Treasury Stock Shares	6.521M shares	5.806M shares
Shareholders Equity	$746.3M	$761.0M
YoY Change
Total Liabilities & Shareholders Equity	$1.422B	$1.424B
YoY Change	-0.12%	2.68%

Cashflow Statement

Concept	2019 Q2	2018 Q2
OPERATING ACTIVITIES
Net Income	$19.20M	$20.70M
YoY Change	-7.25%	340.43%
Depreciation, Depletion And Amortization	$12.10M	$10.90M
YoY Change	11.01%	14.74%
Cash From Operating Activities	$47.70M	$57.90M
YoY Change	-17.62%	-16.09%
INVESTING ACTIVITIES
Capital Expenditures	-$16.30M	-$16.10M
YoY Change	1.24%	-35.34%
Acquisitions
YoY Change
Other Investing Activities	-$2.400M	$11.40M
YoY Change	-121.05%	-43.0%
Cash From Investing Activities	-$18.70M	-$4.700M
YoY Change	297.87%	-4.08%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-21.50M	-22.60M
YoY Change	-4.87%	-44.06%
NET CHANGE
Cash From Operating Activities	47.70M	57.90M
Cash From Investing Activities	-18.70M	-4.700M
Cash From Financing Activities	-21.50M	-22.60M
Net Change In Cash	7.500M	30.60M
YoY Change	-75.49%	29.11%
FREE CASH FLOW
Cash From Operating Activities	$47.70M	$57.90M
Capital Expenditures	-$16.30M	-$16.10M
Free Cash Flow	$64.00M	$74.00M
YoY Change	-13.51%	-21.19%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
	dei	Amendment Flag AmendmentFlag	false
	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q2
	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2019
	dei	Entity Central Index Key EntityCentralIndexKey	0000811596
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CY2019Q2	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	90000000	shares
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CY2019Q2	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	22549931	shares
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CY2019Q2	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	16028675	shares
CY2018Q2	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	400000	USD
	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	900000	USD
CY2018Q4	us-gaap	Margin Deposit Assets MarginDepositAssets	0	USD
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	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2019-06-30
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity File Number EntityFileNumber	1-09447
	dei	Entity Registrant Name EntityRegistrantName	KAISER ALUMINUM CORPORATION
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	94-3030279
	dei	Entity Address Address Line1 EntityAddressAddressLine1	27422 Portola Parkway,
	dei	Entity Address Address Line2 EntityAddressAddressLine2	Suite 200
	dei	Entity Address City Or Town EntityAddressCityOrTown	Foothill Ranch,
	dei	Entity Address State Or Province EntityAddressStateOrProvince	CA
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	92610-2831
	dei	City Area Code CityAreaCode	(949)
	dei	Local Phone Number LocalPhoneNumber	614-1740
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Entity Small Business EntitySmallBusiness	false
	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
	dei	Entity Shell Company EntityShellCompany	false
	dei	Security12b Title Security12bTitle	Common stock, par value $0.01 per share
	dei	Trading Symbol TradingSymbol	KALU
	dei	Security Exchange Name SecurityExchangeName	NASDAQ
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CY2019Q2	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	26000000.0	USD
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CY2019Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-3200000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	6400000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	6500000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-1900000	USD
CY2019Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	16000000.0	USD
CY2018Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	27100000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	53700000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	44500000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	740400000	USD
CY2019Q1	us-gaap	Net Income Loss NetIncomeLoss	28000000.0	USD
CY2019Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	9700000	USD
CY2019Q1	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	5000000.0	USD
CY2019Q1	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	17400000	USD
CY2019Q1	us-gaap	Dividends Cash DividendsCash	10200000	USD
CY2019Q1	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	2400000	USD
CY2019Q1	us-gaap	Stockholders Equity StockholdersEquity	747900000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	19200000	USD
CY2019Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-3200000	USD
CY2019Q2	us-gaap	Stock Issued During Period Value Issued For Services StockIssuedDuringPeriodValueIssuedForServices	300000	USD
CY2019Q2	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	1200000	USD
CY2019Q2	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	10200000	USD
CY2019Q2	us-gaap	Dividends Cash DividendsCash	9900000	USD
CY2019Q2	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	3400000	USD
CY2019Q2	us-gaap	Stockholders Equity StockholdersEquity	746300000	USD
CY2019Q1	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	98.55
CY2019Q2	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	95.00
CY2019Q2	us-gaap	Stock Repurchase Program Remaining Authorized Repurchase Amount1 StockRepurchaseProgramRemainingAuthorizedRepurchaseAmount1	121000000.0	USD
CY2019Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.60
CY2017Q4	us-gaap	Stockholders Equity StockholdersEquity	746300000	USD
CY2017Q4	us-gaap	Cumulative Effect Of New Accounting Principle In Period Of Adoption CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	10100000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest Adjusted Balance1 StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestAdjustedBalance1	756400000	USD
CY2018Q1	us-gaap	Net Income Loss NetIncomeLoss	25700000	USD
CY2018Q1	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-8300000	USD
CY2018Q1	us-gaap	Stock Repurchased And Retired During Period Value StockRepurchasedAndRetiredDuringPeriodValue	6900000	USD
CY2018Q1	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	6100000	USD
CY2018Q1	us-gaap	Dividends Cash DividendsCash	10000000.0	USD
CY2018Q1	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	2800000	USD
CY2018Q1	us-gaap	Stockholders Equity StockholdersEquity	753600000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	20700000	USD
CY2018Q2	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	6400000	USD
CY2018Q2	us-gaap	Stock Issued During Period Value Issued For Services StockIssuedDuringPeriodValueIssuedForServices	200000	USD
CY2018Q2	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	13300000	USD
CY2018Q2	us-gaap	Dividends Cash DividendsCash	9300000	USD
CY2018Q2	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	2700000	USD
CY2018Q2	us-gaap	Stockholders Equity StockholdersEquity	761000000.0	USD
CY2018Q1	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	104.50
CY2018Q2	us-gaap	Treasury Stock Acquired Average Cost Per Share TreasuryStockAcquiredAverageCostPerShare	104.74
CY2018Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.55
	us-gaap	Net Income Loss NetIncomeLoss	47200000	USD
	us-gaap	Net Income Loss NetIncomeLoss	46400000	USD
	us-gaap	Depreciation Depreciation	22600000	USD
	us-gaap	Depreciation Depreciation	20700000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1400000	USD
	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	700000	USD
	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	600000	USD
	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	500000	USD
	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	18300000	USD
	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	17800000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	6100000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	5700000	USD
	us-gaap	Gain Loss On Sale Of Investments GainLossOnSaleOfInvestments	400000	USD
	us-gaap	Gain Loss On Sale Of Investments GainLossOnSaleOfInvestments	1500000	USD
	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	100000	USD
	us-gaap	Goodwill And Intangible Asset Impairment GoodwillAndIntangibleAssetImpairment	100000	USD
	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	200000	USD
	us-gaap	Gain Loss On Sale Of Property Plant Equipment GainLossOnSaleOfPropertyPlantEquipment	-100000	USD
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-6100000	USD
	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-15700000	USD
	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	-2200000	USD
	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	29600000	USD
	us-gaap	Increase Decrease In Contract Receivables Net IncreaseDecreaseInContractReceivablesNet	-8000000.0	USD
	us-gaap	Increase Decrease In Contract Receivables Net IncreaseDecreaseInContractReceivablesNet	-3000000.0	USD
	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	16000000.0	USD
	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	10000000.0	USD
	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	4300000	USD
	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	3000000.0	USD
	us-gaap	Increase Decrease In Accounts Payable Trade IncreaseDecreaseInAccountsPayableTrade	-13400000	USD
	us-gaap	Increase Decrease In Accounts Payable Trade IncreaseDecreaseInAccountsPayableTrade	43900000	USD
	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	-6600000	USD
	us-gaap	Increase Decrease In Other Accrued Liabilities IncreaseDecreaseInOtherAccruedLiabilities	-10800000	USD
	us-gaap	Other Postretirement Benefits Payments OtherPostretirementBenefitsPayments	2100000	USD
	us-gaap	Other Postretirement Benefits Payments OtherPostretirementBenefitsPayments	15700000	USD
	us-gaap	Increase Decrease In Other Noncurrent Assets And Liabilities Net IncreaseDecreaseInOtherNoncurrentAssetsAndLiabilitiesNet	-900000	USD
	us-gaap	Increase Decrease In Other Noncurrent Assets And Liabilities Net IncreaseDecreaseInOtherNoncurrentAssetsAndLiabilitiesNet	0	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	70500000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	84000000.0	USD
	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	29900000	USD
	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	35800000	USD
	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	33000000.0	USD
	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	24000000.0	USD
	us-gaap	Payments To Acquire Available For Sale Securities Equity PaymentsToAcquireAvailableForSaleSecuritiesEquity	700000	USD
	us-gaap	Payments To Acquire Available For Sale Securities Equity PaymentsToAcquireAvailableForSaleSecuritiesEquity	900000	USD
	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	45700000	USD
	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	136600000	USD
	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	200000	USD
	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	0	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-17700000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	75900000	USD
	us-gaap	Repayments Of Long Term Capital Lease Obligations RepaymentsOfLongTermCapitalLeaseObligations	600000	USD
	us-gaap	Repayments Of Long Term Capital Lease Obligations RepaymentsOfLongTermCapitalLeaseObligations	300000	USD
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	6200000	USD
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	6900000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	28600000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	18900000	USD
	us-gaap	Payments Of Dividends PaymentsOfDividends	20100000	USD
	us-gaap	Payments Of Dividends PaymentsOfDividends	19300000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-55500000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-45400000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-2700000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	114500000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	139600000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	64300000	USD
CY2019Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	136900000	USD
CY2018Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	178800000	USD
	us-gaap	Use Of Estimates UseOfEstimates	<span style="font-family:inherit;font-size:10pt;font-style:italic;">Use of Estimates in the Preparation of Financial Statements.</span> The preparation of financial statements in accordance with GAAP requires the use of estimates and assumptions that affect the reported amounts of assets and liabilities, disclosure of contingent assets and liabilities known to exist as of the date the financial statements are published and the reported amounts of revenues and expenses during the reporting period. Uncertainties with respect to such estimates and assumptions are inherent in the preparation of our consolidated financial statements; accordingly, it is possible that the actual results could differ from these estimates and assumptions, which could have a material effect on the reported amounts of our consolidated financial position and results of operations.
CY2019Q2	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	24700000	USD
CY2018Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	27500000	USD
CY2019Q2	us-gaap	Liabilities Other Than Longterm Debt Noncurrent LiabilitiesOtherThanLongtermDebtNoncurrent	63200000	USD
CY2018Q4	us-gaap	Liabilities Other Than Longterm Debt Noncurrent LiabilitiesOtherThanLongtermDebtNoncurrent	66400000	USD
CY2019Q2	us-gaap	Excess Of Replacement Or Current Costs Over Stated Lifo Value ExcessOfReplacementOrCurrentCostsOverStatedLIFOValue	12800000	USD
CY2018Q4	us-gaap	Excess Of Replacement Or Current Costs Over Stated Lifo Value ExcessOfReplacementOrCurrentCostsOverStatedLIFOValue	31700000	USD
CY2019Q2	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	400000	USD
	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	900000	USD
CY2019Q2	kalu	Workerscompensationliabilityundiscounted Workerscompensationliabilityundiscounted	27200000	USD
CY2018Q4	kalu	Workerscompensationliabilityundiscounted Workerscompensationliabilityundiscounted	27600000	USD
	us-gaap	Workers Compensation Discount Percent WorkersCompensationDiscountPercent	0.0200
CY2018	us-gaap	Workers Compensation Discount Percent WorkersCompensationDiscountPercent	0.0300
CY2019Q2	us-gaap	Accrued Employee Benefits Current And Noncurrent AccruedEmployeeBenefitsCurrentAndNoncurrent	3300000	USD
CY2018Q4	us-gaap	Accrued Employee Benefits Current And Noncurrent AccruedEmployeeBenefitsCurrentAndNoncurrent	3600000	USD
CY2019Q2	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Available For Grant ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant	481924	shares
CY2019Q2	us-gaap	Cash Cash	32200000	USD
CY2018Q4	us-gaap	Cash Cash	22900000	USD
CY2019Q2	us-gaap	Commercial Paper At Carrying Value CommercialPaperAtCarryingValue	90200000	USD
CY2018Q4	us-gaap	Commercial Paper At Carrying Value CommercialPaperAtCarryingValue	102700000	USD
CY2019Q2	us-gaap	Cash Cash Equivalents And Short Term Investments CashCashEquivalentsAndShortTermInvestments	122400000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents And Short Term Investments CashCashEquivalentsAndShortTermInvestments	125600000	USD
CY2019Q2	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	178900000	USD
CY2018Q4	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	180600000	USD
CY2019Q2	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	800000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	800000	USD
CY2019Q2	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	178100000	USD
CY2018Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	179800000	USD
CY2019Q2	us-gaap	Inventory Finished Goods InventoryFinishedGoods	44200000	USD
CY2018Q4	us-gaap	Inventory Finished Goods InventoryFinishedGoods	48000000.0	USD
CY2019Q2	us-gaap	Inventory Work In Process InventoryWorkInProcess	98500000	USD
CY2018Q4	us-gaap	Inventory Work In Process InventoryWorkInProcess	85600000	USD
CY2019Q2	us-gaap	Inventory Raw Materials InventoryRawMaterials	81000000.0	USD
CY2018Q4	us-gaap	Inventory Raw Materials InventoryRawMaterials	75000000.0	USD
CY2019Q2	us-gaap	Other Inventory Supplies OtherInventorySupplies	7400000	USD
CY2018Q4	us-gaap	Other Inventory Supplies OtherInventorySupplies	6500000	USD
CY2019Q2	us-gaap	Inventory Net InventoryNet	231100000	USD
CY2018Q4	us-gaap	Inventory Net InventoryNet	215100000	USD
CY2019Q2	us-gaap	Land Land	21400000	USD
CY2018Q4	us-gaap	Land Land	21400000	USD
CY2019Q2	us-gaap	Buildings And Improvements Gross BuildingsAndImprovementsGross	98700000	USD
CY2018Q4	us-gaap	Buildings And Improvements Gross BuildingsAndImprovementsGross	97000000.0	USD
CY2019Q2	us-gaap	Machinery And Equipment Gross MachineryAndEquipmentGross	783600000	USD
CY2018Q4	us-gaap	Machinery And Equipment Gross MachineryAndEquipmentGross	755600000	USD
CY2019Q2	us-gaap	Construction In Progress Gross ConstructionInProgressGross	38100000	USD
CY2018Q4	us-gaap	Construction In Progress Gross ConstructionInProgressGross	43600000	USD
CY2019Q2	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	941800000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	917600000	USD
CY2019Q2	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	329600000	USD
CY2018Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	307400000	USD
CY2019Q2	us-gaap	Assets Held For Sale Not Part Of Disposal Group AssetsHeldForSaleNotPartOfDisposalGroup	1600000	USD
CY2018Q4	us-gaap	Assets Held For Sale Not Part Of Disposal Group AssetsHeldForSaleNotPartOfDisposalGroup	1600000	USD
CY2019Q2	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	613800000	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	611800000	USD
CY2019Q2	us-gaap	Bank Overdrafts BankOverdrafts	3500000	USD
CY2018Q4	us-gaap	Bank Overdrafts BankOverdrafts	4800000	USD
CY2019Q2	us-gaap	Taxes Payable Current TaxesPayableCurrent	7800000	USD
CY2018Q4	us-gaap	Taxes Payable Current TaxesPayableCurrent	6500000	USD
CY2019Q2	kalu	Accrued Annual Veba Contribution AccruedAnnualVebaContribution	0	USD
CY2018Q4	kalu	Accrued Annual Veba Contribution AccruedAnnualVebaContribution	2100000	USD
CY2019Q2	us-gaap	Interest Payable Current InterestPayableCurrent	2900000	USD
CY2018Q4	us-gaap	Interest Payable Current InterestPayableCurrent	2900000	USD
CY2019Q2	us-gaap	Accrued Liabilities And Other Liabilities AccruedLiabilitiesAndOtherLiabilities	33000000.0	USD
CY2018Q4	us-gaap	Accrued Liabilities And Other Liabilities AccruedLiabilitiesAndOtherLiabilities	27700000	USD
CY2019Q2	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	47200000	USD
CY2018Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	44000000.0	USD
CY2019Q2	us-gaap	Self Insurance Reserve Noncurrent SelfInsuranceReserveNoncurrent	25900000	USD
CY2018Q4	us-gaap	Self Insurance Reserve Noncurrent SelfInsuranceReserveNoncurrent	24600000	USD
CY2019Q2	us-gaap	Accrued Environmental Loss Contingencies Noncurrent AccruedEnvironmentalLossContingenciesNoncurrent	12600000	USD
CY2018Q4	us-gaap	Accrued Environmental Loss Contingencies Noncurrent AccruedEnvironmentalLossContingenciesNoncurrent	14300000	USD
CY2019Q2	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.044
CY2019Q2	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.058
CY2019Q2	us-gaap	Lessee Operating Lease Renewal Term LesseeOperatingLeaseRenewalTerm	P20Y
	kalu	Lessee Operating Lease Optionto Terminate Duration LesseeOperatingLeaseOptiontoTerminateDuration	P1Y
CY2019Q2	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P6Y4M24D
CY2019Q2	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P10Y9M18D
CY2019Q2	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	26800000	USD
CY2019Q2	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	6900000	USD
CY2019Q2	kalu	Rightof Use Asset Total RightofUseAssetTotal	33700000	USD
CY2019Q2	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	3600000	USD
CY2019Q2	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	1200000	USD
CY2019Q2	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	26000000.0	USD
CY2019Q2	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	5700000	USD
CY2019Q2	kalu	Lease Liability Total LeaseLiabilityTotal	36500000	USD
CY2019Q2	us-gaap	Operating Lease Cost OperatingLeaseCost	1800000	USD
	us-gaap	Operating Lease Cost OperatingLeaseCost	3800000	USD
CY2019Q2	us-gaap	Short Term Lease Cost ShortTermLeaseCost	200000	USD
	us-gaap	Short Term Lease Cost ShortTermLeaseCost	500000	USD
CY2019Q2	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	300000	USD
	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	700000	USD
CY2019Q2	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	100000	USD
	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	200000	USD
CY2019Q2	us-gaap	Lease Cost LeaseCost	2400000	USD
	us-gaap	Lease Cost LeaseCost	5200000	USD
CY2019Q2	us-gaap	Finance Lease Liability Payments Remainder Of Fiscal Year FinanceLeaseLiabilityPaymentsRemainderOfFiscalYear	800000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Remainder Of Fiscal Year LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear	2600000	USD
CY2019Q2	kalu	Finance Lease Liability Payments Due Year One FinanceLeaseLiabilityPaymentsDueYearOne	1400000	USD
CY2019Q2	kalu	Operating Lease Liability Payments Due Year One OperatingLeaseLiabilityPaymentsDueYearOne	4900000	USD
CY2019Q2	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	1200000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	4200000	USD
CY2019Q2	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	1100000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	3600000	USD
CY2019Q2	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	1100000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	3400000	USD
CY2019Q2	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	800000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	3300000	USD
CY2019Q2	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	1600000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	18600000	USD
CY2019Q2	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	8000000.0	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	40600000	USD
CY2019Q2	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	1100000	USD
CY2019Q2	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	11000000.0	USD
CY2019Q2	us-gaap	Finance Lease Liability FinanceLeaseLiability	6900000	USD
CY2019Q2	us-gaap	Operating Lease Liability OperatingLeaseLiability	29600000	USD
CY2018Q4	us-gaap	Capital Leases Future Minimum Payments Due Current CapitalLeasesFutureMinimumPaymentsDueCurrent	1700000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Current OperatingLeasesFutureMinimumPaymentsDueCurrent	6100000	USD
CY2018Q4	us-gaap	Capital Leases Future Minimum Payments Due In Two Years CapitalLeasesFutureMinimumPaymentsDueInTwoYears	1400000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Two Years OperatingLeasesFutureMinimumPaymentsDueInTwoYears	3700000	USD
CY2018Q4	us-gaap	Capital Leases Future Minimum Payments Due In Three Years CapitalLeasesFutureMinimumPaymentsDueInThreeYears	1200000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Three Years OperatingLeasesFutureMinimumPaymentsDueInThreeYears	2800000	USD
CY2018Q4	us-gaap	Capital Leases Future Minimum Payments Due In Four Years CapitalLeasesFutureMinimumPaymentsDueInFourYears	1100000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Four Years OperatingLeasesFutureMinimumPaymentsDueInFourYears	2400000	USD
CY2018Q4	us-gaap	Capital Leases Future Minimum Payments Due In Five Years CapitalLeasesFutureMinimumPaymentsDueInFiveYears	1000000.0	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due In Five Years OperatingLeasesFutureMinimumPaymentsDueInFiveYears	2200000	USD
CY2018Q4	us-gaap	Capital Leases Future Minimum Payments Due Thereafter CapitalLeasesFutureMinimumPaymentsDueThereafter	1800000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	20800000	USD
CY2018Q4	us-gaap	Capital Leases Future Minimum Payments Due CapitalLeasesFutureMinimumPaymentsDue	8200000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due OperatingLeasesFutureMinimumPaymentsDue	38000000.0	USD
CY2018Q4	us-gaap	Capital Leases Future Minimum Payments Interest Included In Payments CapitalLeasesFutureMinimumPaymentsInterestIncludedInPayments	1200000	USD
CY2018Q4	us-gaap	Capital Lease Obligations CapitalLeaseObligations	7000000.0	USD
CY2018Q4	us-gaap	Capital Lease Obligations CapitalLeaseObligations	7000000.0	USD
CY2018Q4	us-gaap	Capital Leased Assets Gross CapitalLeasedAssetsGross	8300000	USD
CY2018Q4	us-gaap	Capital Leases Lessee Balance Sheet Assets By Major Class Accumulated Deprecation CapitalLeasesLesseeBalanceSheetAssetsByMajorClassAccumulatedDeprecation	1300000	USD
CY2019Q2	us-gaap	Margin Deposit Assets MarginDepositAssets	0	USD
CY2019Q2	us-gaap	Customer Deposits Current CustomerDepositsCurrent	300000	USD
CY2018Q4	us-gaap	Customer Deposits Current CustomerDepositsCurrent	200000	USD
CY2019Q2	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	303500000	USD
	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	618600000	USD
	us-gaap	Debt Instrument Term DebtInstrumentTerm	P12M
CY2019Q2	us-gaap	Accrual For Environmental Loss Contingencies AccrualForEnvironmentalLossContingencies	16700000	USD
	kalu	Expected Period Related To Remediation Expenditures For Environmental Contingencies Period ExpectedPeriodRelatedToRemediationExpendituresForEnvironmentalContingenciesPeriod	P30Y
CY2019Q2	us-gaap	Loss Contingency Range Of Possible Loss Portion Not Accrued LossContingencyRangeOfPossibleLossPortionNotAccrued	11600000	USD
CY2019Q2	kalu	Time Period Within Which Companys Recorded Estimate Of Its Obligation May Change TimePeriodWithinWhichCompanysRecordedEstimateOfItsObligationMayChange	P12M
	us-gaap	Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths	-11900000	USD
CY2019Q2	kalu	Defined Benefit Plan Net Periodic Cost Benefit Veb As DefinedBenefitPlanNetPeriodicCostBenefitVEBAs	1600000	USD
CY2018Q2	kalu	Defined Benefit Plan Net Periodic Cost Benefit Veb As DefinedBenefitPlanNetPeriodicCostBenefitVEBAs	1600000	USD
	kalu	Defined Benefit Plan Net Periodic Cost Benefit Veb As DefinedBenefitPlanNetPeriodicCostBenefitVEBAs	3300000	USD
	kalu	Defined Benefit Plan Net Periodic Cost Benefit Veb As DefinedBenefitPlanNetPeriodicCostBenefitVEBAs	3100000	USD
CY2019Q2	us-gaap	Available For Sale Securities Gross Realized Gain Loss Net AvailableForSaleSecuritiesGrossRealizedGainLossNet	1200000	USD
CY2018Q2	us-gaap	Available For Sale Securities Gross Realized Gain Loss Net AvailableForSaleSecuritiesGrossRealizedGainLossNet	1500000	USD
CY2019Q2	us-gaap	Investment Income Interest InvestmentIncomeInterest	100000	USD
CY2018Q2	us-gaap	Investment Income Interest InvestmentIncomeInterest	0	USD
	us-gaap	Investment Income Interest InvestmentIncomeInterest	300000	USD
	us-gaap	Investment Income Interest InvestmentIncomeInterest	100000	USD
	us-gaap	Available For Sale Securities Gross Realized Gain Loss Net AvailableForSaleSecuritiesGrossRealizedGainLossNet	2400000	USD
	us-gaap	Available For Sale Securities Gross Realized Gain Loss Net AvailableForSaleSecuritiesGrossRealizedGainLossNet	3100000	USD
CY2019Q2	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	0	USD
CY2018Q2	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-400000	USD
	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	500000	USD
	us-gaap	Equity Securities Fv Ni Gain Loss EquitySecuritiesFvNiGainLoss	-400000	USD
CY2019Q2	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	200000	USD
CY2018Q2	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	0	USD
	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	500000	USD
	us-gaap	Other Nonoperating Income OtherNonoperatingIncome	-100000	USD
CY2019Q2	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-100000	USD
CY2018Q2	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-500000	USD
	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	400000	USD
	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-400000	USD
CY2018Q2	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	600000	USD
CY2018Q2	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense EffectiveIncomeTaxRateReconciliationNondeductibleExpense	0.02
CY2018Q2	us-gaap	Income Tax Reconciliation Tax Contingencies State And Local IncomeTaxReconciliationTaxContingenciesStateAndLocal	300000	USD
CY2018Q2	us-gaap	Effective Income Tax Rate Reconciliation Tax Contingencies State And Local EffectiveIncomeTaxRateReconciliationTaxContingenciesStateAndLocal	0.01
CY2019Q2	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	6800000	USD
CY2018Q2	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	7500000	USD
	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	16300000	USD
	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	13100000	USD
CY2019Q2	us-gaap	Foreign Income Tax Expense Benefit Continuing Operations ForeignIncomeTaxExpenseBenefitContinuingOperations	500000	USD
CY2018Q2	us-gaap	Foreign Income Tax Expense Benefit Continuing Operations ForeignIncomeTaxExpenseBenefitContinuingOperations	300000	USD
	us-gaap	Foreign Income Tax Expense Benefit Continuing Operations ForeignIncomeTaxExpenseBenefitContinuingOperations	800000	USD
	us-gaap	Foreign Income Tax Expense Benefit Continuing Operations ForeignIncomeTaxExpenseBenefitContinuingOperations	600000	USD
CY2019Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7300000	USD
CY2018Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7800000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	17100000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	13700000	USD
CY2019Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7300000	USD
CY2018Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7800000	USD
CY2019Q2	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.27
CY2018Q2	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.28
CY2019Q2	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	500000	USD
CY2019Q2	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense EffectiveIncomeTaxRateReconciliationNondeductibleExpense	0.02
CY2019Q2	kalu	Effective Tax Rate Reconciliation Unrecognized Tax Benefit Amount EffectiveTaxRateReconciliationUnrecognizedTaxBenefitAmount	200000	USD
CY2019Q2	kalu	Effective Income Tax Rate Reconciliation Unrecognized Tax Benefit Percent EffectiveIncomeTaxRateReconciliationUnrecognizedTaxBenefitPercent	0.01
CY2018Q2	kalu	Effective Income Tax Rate Reconciliation Sequestrationof Amt Credits Amount EffectiveIncomeTaxRateReconciliationSequestrationofAMTCreditsAmount	200000	USD
CY2018Q2	kalu	Effective Income Tax Rate Reconciliation Sequestrationof Amt Credits Percent EffectiveIncomeTaxRateReconciliationSequestrationofAMTCreditsPercent	0.01
CY2018Q2	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-300000	USD
CY2018Q2	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Percent EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitPercent	-0.01
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	17100000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	13700000	USD
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.27
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.23
	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	900000	USD
	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense EffectiveIncomeTaxRateReconciliationNondeductibleExpense	0.02
	us-gaap	Income Tax Reconciliation Tax Contingencies State And Local IncomeTaxReconciliationTaxContingenciesStateAndLocal	800000	USD
	us-gaap	Effective Income Tax Rate Reconciliation Tax Contingencies State And Local EffectiveIncomeTaxRateReconciliationTaxContingenciesStateAndLocal	0.01
	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-500000	USD
	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Percent EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitPercent	-0.01
	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-2000000.0	USD
	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Percent EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitPercent	-0.03
	us-gaap	Income Tax Reconciliation Tax Contingencies State And Local IncomeTaxReconciliationTaxContingenciesStateAndLocal	-500000	USD
	us-gaap	Effective Income Tax Rate Reconciliation Tax Contingencies State And Local EffectiveIncomeTaxRateReconciliationTaxContingenciesStateAndLocal	-0.01
	us-gaap	Income Tax Reconciliation Nondeductible Expense IncomeTaxReconciliationNondeductibleExpense	1200000	USD
	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense EffectiveIncomeTaxRateReconciliationNondeductibleExpense	0.02
	kalu	Effective Income Tax Rate Reconciliation Sequestrationof Amt Credits Amount EffectiveIncomeTaxRateReconciliationSequestrationofAMTCreditsAmount	400000	USD
	kalu	Effective Income Tax Rate Reconciliation Sequestrationof Amt Credits Percent EffectiveIncomeTaxRateReconciliationSequestrationofAMTCreditsPercent	0.01
CY2019Q2	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1700000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1500000	USD
CY2019Q2	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	600000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	400000	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	19200000	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	20700000	USD
	us-gaap	Net Income Loss NetIncomeLoss	47200000	USD
	us-gaap	Net Income Loss NetIncomeLoss	46400000	USD
CY2019Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16063000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16685000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16085000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	16696000	shares
CY2019Q2	us-gaap	Incremental Common Shares Attributable To Nonvested Shares With Forfeitable Dividends IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends	177000	shares
CY2018Q2	us-gaap	Incremental Common Shares Attributable To Nonvested Shares With Forfeitable Dividends IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends	220000	shares
	us-gaap	Incremental Common Shares Attributable To Nonvested Shares With Forfeitable Dividends IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends	213000	shares
	us-gaap	Incremental Common Shares Attributable To Nonvested Shares With Forfeitable Dividends IncrementalCommonSharesAttributableToNonvestedSharesWithForfeitableDividends	266000	shares
CY2019Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	16240000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	16905000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	16298000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	16962000	shares
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.19
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.24
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.93
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.78
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.18
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.22
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.89
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.74
CY2019Q2	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	9000	shares
CY2019Q2	kalu	Percentageof Employees Coveredby Collective Bargaining Agreements Expiring Within One Year PercentageofEmployeesCoveredbyCollectiveBargainingAgreementsExpiringWithinOneYear	0.01
CY2019Q2	us-gaap	Revenues Revenues	375300000	USD
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	5000	shares
CY2018Q2	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	2000	shares
	us-gaap	Antidilutive Securities Excluded From Computation Of Earnings Per Share Amount AntidilutiveSecuritiesExcludedFromComputationOfEarningsPerShareAmount	1000	shares
	us-gaap	Interest Paid Net InterestPaidNet	10700000	USD
	us-gaap	Interest Paid Net InterestPaidNet	10700000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	2400000	USD
	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	5100000	USD
	us-gaap	Other Significant Noncash Transaction Value Of Consideration Given1 OtherSignificantNoncashTransactionValueOfConsiderationGiven1	300000	USD
	us-gaap	Other Significant Noncash Transaction Value Of Consideration Given1 OtherSignificantNoncashTransactionValueOfConsiderationGiven1	600000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	900000	USD
	us-gaap	Operating Lease Payments OperatingLeasePayments	1800000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	500000	USD
	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	300000	USD
CY2019Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	122400000	USD
CY2018Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	164000000.0	USD
CY2019Q2	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	300000	USD
CY2018Q2	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	300000	USD
CY2019Q2	us-gaap	Restricted Cash And Cash Equivalents Noncurrent RestrictedCashAndCashEquivalentsNoncurrent	14200000	USD
CY2018Q2	us-gaap	Restricted Cash And Cash Equivalents Noncurrent RestrictedCashAndCashEquivalentsNoncurrent	14500000	USD
CY2019Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	136900000	USD
CY2018Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	178800000	USD
CY2019Q2	kalu	Percentageof Employees Coveredby Collective Bargaining Agreements PercentageofEmployeesCoveredbyCollectiveBargainingAgreements	0.62
CY2018Q2	us-gaap	Revenues Revenues	415400000	USD
	us-gaap	Revenues Revenues	770500000	USD
	us-gaap	Revenues Revenues	803400000	USD
CY2019Q2	us-gaap	Revenues Revenues	375300000	USD
CY2018Q2	us-gaap	Revenues Revenues	415400000	USD
	us-gaap	Revenues Revenues	770500000	USD
	us-gaap	Revenues Revenues	803400000	USD
CY2019Q2	kalu	Ownership Interest In Subsidiaries OwnershipInterestInSubsidiaries	1
CY2019Q2	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	122400000	USD
CY2019Q2	us-gaap	Contract With Customer Asset Net Current ContractWithCustomerAssetNetCurrent	46900000	USD
CY2019Q2	us-gaap	Inventory Net InventoryNet	231100000	USD
CY2019Q2	us-gaap	Prepaid Expense And Other Assets Current PrepaidExpenseAndOtherAssetsCurrent	21700000	USD
CY2019Q2	us-gaap	Assets Current AssetsCurrent	649700000	USD
CY2019Q2	us-gaap	Available For Sale Securities Current AvailableForSaleSecuritiesCurrent	24400000	USD
CY2019Q2	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	178100000	USD
CY2019Q2	kalu	Intercompany Receivables Current IntercompanyReceivablesCurrent	0	USD
CY2019Q2	us-gaap	Other Receivables OtherReceivables	25100000	USD
CY2019Q2	us-gaap	Income Taxes Paid IncomeTaxesPaid	2200000	USD
CY2018Q2	us-gaap	Income Taxes Paid IncomeTaxesPaid	2700000	USD
	us-gaap	Income Taxes Paid IncomeTaxesPaid	3100000	USD
	us-gaap	Income Taxes Paid IncomeTaxesPaid	2900000	USD
CY2019Q2	us-gaap	Investments In And Advances To Affiliates At Fair Value InvestmentsInAndAdvancesToAffiliatesAtFairValue	0	USD
CY2019Q2	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	613800000	USD
CY2019Q2	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	26800000	USD
CY2019Q2	kalu	Intercompany Receivables Noncurrent IntercompanyReceivablesNoncurrent	0	USD
CY2019Q2	us-gaap	Deferred Tax Assets Net Noncurrent DeferredTaxAssetsNetNoncurrent	15500000	USD
CY2019Q2	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	31000000.0	USD
CY2019Q2	us-gaap	Goodwill Goodwill	44000000.0	USD
CY2019Q2	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	41300000	USD
CY2019Q2	us-gaap	Assets Assets	1422100000	USD
CY2019Q2	us-gaap	Accounts Payable Current AccountsPayableCurrent	101300000	USD
CY2018Q4	us-gaap	Contract With Customer Asset Net Current ContractWithCustomerAssetNetCurrent	54900000	USD
CY2018Q4	us-gaap	Inventory Net InventoryNet	215100000	USD
CY2018Q4	us-gaap	Prepaid Expense And Other Assets Current PrepaidExpenseAndOtherAssetsCurrent	18900000	USD
CY2018Q4	us-gaap	Deferred Tax Assets Net Noncurrent DeferredTaxAssetsNetNoncurrent	35900000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	32400000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	44000000.0	USD
CY2018Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	38600000	USD
CY2018Q4	us-gaap	Assets Current AssetsCurrent	656600000	USD
CY2018Q4	us-gaap	Investments In And Advances To Affiliates At Fair Value InvestmentsInAndAdvancesToAffiliatesAtFairValue	0	USD
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	611800000	USD
CY2018Q4	kalu	Intercompany Receivables Noncurrent IntercompanyReceivablesNoncurrent	0	USD
CY2019Q2	kalu	Intercompany Payable Current IntercompanyPayableCurrent	0	USD
CY2019Q2	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	30400000	USD
CY2019Q2	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	47200000	USD
CY2019Q2	us-gaap	Liabilities Current LiabilitiesCurrent	178900000	USD
CY2019Q2	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	26000000.0	USD
CY2019Q2	kalu	Net Liability In Respect Of Veba NetLiabilityInRespectOfVeba	32600000	USD
CY2019Q2	us-gaap	Deferred Tax Liabilities Gross Noncurrent DeferredTaxLiabilitiesGrossNoncurrent	4200000	USD
CY2019Q2	kalu	Intercompany Payable Noncurrent IntercompanyPayableNoncurrent	0	USD
CY2019Q2	us-gaap	Liabilities Other Than Longterm Debt Noncurrent LiabilitiesOtherThanLongtermDebtNoncurrent	63200000	USD
CY2019Q2	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	370900000	USD
CY2019Q2	us-gaap	Liabilities Liabilities	675800000	USD
CY2019Q2	us-gaap	Stockholders Equity StockholdersEquity	746300000	USD
CY2019Q2	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	1422100000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	125600000	USD
CY2018Q4	us-gaap	Available For Sale Securities Current AvailableForSaleSecuritiesCurrent	36700000	USD
CY2018Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	179800000	USD
CY2018Q4	kalu	Intercompany Receivables Current IntercompanyReceivablesCurrent	0	USD
CY2018Q4	us-gaap	Other Receivables OtherReceivables	25600000	USD
CY2018Q4	us-gaap	Assets Assets	1419300000	USD
CY2018Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	121400000	USD
CY2018Q4	kalu	Intercompany Payable Current IntercompanyPayableCurrent	0	USD
CY2018Q4	us-gaap	Employee Related Liabilities Current EmployeeRelatedLiabilitiesCurrent	40100000	USD
CY2018Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	44000000.0	USD
CY2018Q4	us-gaap	Liabilities Current LiabilitiesCurrent	205500000	USD
CY2018Q4	kalu	Net Liability In Respect Of Veba NetLiabilityInRespectOfVeba	32400000	USD
CY2018Q4	us-gaap	Deferred Tax Liabilities Gross Noncurrent DeferredTaxLiabilitiesGrossNoncurrent	4200000	USD
CY2018Q4	kalu	Intercompany Payable Noncurrent IntercompanyPayableNoncurrent	0	USD
CY2018Q4	us-gaap	Liabilities Other Than Longterm Debt Noncurrent LiabilitiesOtherThanLongtermDebtNoncurrent	66400000	USD
CY2018Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	370400000	USD
CY2018Q4	us-gaap	Liabilities Liabilities	678900000	USD
CY2018Q4	us-gaap	Stockholders Equity StockholdersEquity	740400000	USD
CY2018Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	1419300000	USD
CY2019Q2	us-gaap	Revenues Revenues	375300000	USD
CY2019Q2	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	303500000	USD
CY2019Q2	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	12100000	USD
CY2019Q2	kalu	Selling Administrative Research And Development And General Expenses SellingAdministrativeResearchAndDevelopmentAndGeneralExpenses	27200000	USD
CY2019Q2	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	100000	USD
CY2019Q2	us-gaap	Costs And Expenses CostsAndExpenses	342900000	USD
CY2019Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	32400000	USD
CY2019Q2	us-gaap	Interest Expense InterestExpense	5800000	USD
CY2019Q2	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-100000	USD
CY2019Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	26500000	USD
CY2019Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7300000	USD
CY2019Q2	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	0	USD
CY2019Q2	us-gaap	Net Income Loss NetIncomeLoss	19200000	USD
CY2019Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	16000000.0	USD
CY2018Q2	us-gaap	Revenues Revenues	415400000	USD
CY2018Q2	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	343400000	USD
CY2018Q2	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	10900000	USD
CY2018Q2	kalu	Selling Administrative Research And Development And General Expenses SellingAdministrativeResearchAndDevelopmentAndGeneralExpenses	26400000	USD
CY2018Q2	us-gaap	Costs And Expenses CostsAndExpenses	380700000	USD
CY2018Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	34700000	USD
CY2018Q2	us-gaap	Interest Expense InterestExpense	5700000	USD
CY2018Q2	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-500000	USD
CY2018Q2	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	28500000	USD
CY2018Q2	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7800000	USD
CY2018Q2	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	0	USD
CY2018Q2	us-gaap	Net Income Loss NetIncomeLoss	20700000	USD
CY2018Q2	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	27100000	USD
	us-gaap	Revenues Revenues	770500000	USD
	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	618600000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	24000000.0	USD
	kalu	Selling Administrative Research And Development And General Expenses SellingAdministrativeResearchAndDevelopmentAndGeneralExpenses	52400000	USD
	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	100000	USD
	us-gaap	Costs And Expenses CostsAndExpenses	695100000	USD
	us-gaap	Operating Income Loss OperatingIncomeLoss	75400000	USD
	us-gaap	Interest Expense InterestExpense	11500000	USD
	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	400000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	64300000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	17100000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	0	USD
	us-gaap	Net Income Loss NetIncomeLoss	47200000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	53700000	USD
	us-gaap	Revenues Revenues	803400000	USD
	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	660100000	USD
	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	21400000	USD
	kalu	Selling Administrative Research And Development And General Expenses SellingAdministrativeResearchAndDevelopmentAndGeneralExpenses	50000000.0	USD
	us-gaap	Other Cost And Expense Operating OtherCostAndExpenseOperating	100000	USD
	us-gaap	Costs And Expenses CostsAndExpenses	731600000	USD
	us-gaap	Operating Income Loss OperatingIncomeLoss	71800000	USD
	us-gaap	Interest Expense InterestExpense	11300000	USD
	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	-400000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments IncomeLossFromContinuingOperationsBeforeIncomeTaxesMinorityInterestAndIncomeLossFromEquityMethodInvestments	60100000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	13700000	USD
	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	0	USD
	us-gaap	Net Income Loss NetIncomeLoss	46400000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	44500000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	70500000	USD
	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	29900000	USD
	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	33000000.0	USD
	us-gaap	Payments To Acquire Available For Sale Securities Equity PaymentsToAcquireAvailableForSaleSecuritiesEquity	700000	USD
	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	45700000	USD
	us-gaap	Proceeds From Sale Of Property Plant And Equipment ProceedsFromSaleOfPropertyPlantAndEquipment	200000	USD
	kalu	Changein Intercompany Loans Receivable ChangeinIntercompanyLoansReceivable	0	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-17700000	USD
	us-gaap	Repayments Of Long Term Capital Lease Obligations RepaymentsOfLongTermCapitalLeaseObligations	600000	USD
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	6200000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	28600000	USD
	us-gaap	Payments Of Dividends PaymentsOfDividends	20100000	USD
	kalu	Changein Intercompany Loans Payable ChangeinIntercompanyLoansPayable	0	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-55500000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-2700000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	139600000	USD
CY2019Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	136900000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	84000000.0	USD
	us-gaap	Payments To Acquire Productive Assets PaymentsToAcquireProductiveAssets	35800000	USD
	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	24000000.0	USD
	us-gaap	Payments To Acquire Available For Sale Securities Equity PaymentsToAcquireAvailableForSaleSecuritiesEquity	900000	USD
	us-gaap	Proceeds From Sale And Maturity Of Available For Sale Securities ProceedsFromSaleAndMaturityOfAvailableForSaleSecurities	136600000	USD
	kalu	Changein Intercompany Loans Receivable ChangeinIntercompanyLoansReceivable	0	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	75900000	USD
	us-gaap	Repayments Of Long Term Capital Lease Obligations RepaymentsOfLongTermCapitalLeaseObligations	300000	USD
	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	6900000	USD
	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	18900000	USD
	us-gaap	Cash Dividends Paid To Parent Company By Consolidated Subsidiaries CashDividendsPaidToParentCompanyByConsolidatedSubsidiaries	0	USD
	us-gaap	Payments Of Dividends PaymentsOfDividends	19300000	USD
	kalu	Changein Intercompany Loans Payable ChangeinIntercompanyLoansPayable	0	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-45400000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	114500000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	64300000	USD
CY2018Q2	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	178800000	USD

Files In Submission

Name	View Source	Status
0000811596-19-000044-index-headers.html	Edgar Link	pending
0000811596-19-000044-index.html	Edgar Link	pending
0000811596-19-000044.txt	Edgar Link	pending
0000811596-19-000044-xbrl.zip	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
kalu-20190630.xsd	Edgar Link	pending
kalu-20190630_cal.xml	Edgar Link	unprocessable
kalu-20190630_def.xml	Edgar Link	unprocessable
kalu-20190630_lab.xml	Edgar Link	unprocessable
kalu-20190630_pre.xml	Edgar Link	unprocessable
kalu630201910-q.htm	Edgar Link	pending
kalu630201910-q_htm.xml	Edgar Link	completed
kaluexhibit311-6302019.htm	Edgar Link	pending
kaluexhibit312-6302019.htm	Edgar Link	pending
kaluexhibit321-6302019.htm	Edgar Link	pending
kaluexhibit322-6302019.htm	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
R1.htm	Edgar Link	pending
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report.css	Edgar Link	pending
Show.js	Edgar Link	pending

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$KALU
KAISER ALUMINUM CORP Stock $kalu

2019 Q2 Form 10-Q Financial Statement

#000081159619000044 Filed on July 26, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$KALU KAISER ALUMINUM CORP Stock $kalu

2019 Q2 Form 10-Q Financial Statement

#000081159619000044 Filed on July 26, 2019

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$KALU
KAISER ALUMINUM CORP Stock $kalu